ok, I've been through shifted's injector scale and rc engineerings website about 25 times and I still cannot figure this damn thing out. If someone can please shed some light on me so I can get my car to idle that would be great. I just faked the 2 bar upgrade and now the car will not idle no matter what the constant is at. On to the #'s!!!!
Since I dropped my fuel pressure to 40psi, means I need to change the flow rates of the injectors correct? so this means,
Stock injectors @40psi=
The square root of new pressure/old pressure* old flow rate= new flow rate
square root of 40/52* 252CC
=.76923 squared
=.87705* 252CC
=221CC for stock injectors
Brown tops @40psi=
Square root of 40/43.5psi(since ford rates their injectors at 43.5)*367.5CC
=.91954 squared
=.95892*367.5CC
=352CC for brown tops
Then I did this:
Injector Constant = Old Constant * (Old Injector Size / New Injector Size)
injector Constant = .20014* (24/35) or .20014*(221/352) =
.12565 for my injector constant??? Either I'm losing my mind or my tune is just that messed up from the 2 bar fake but I'm about to go crazy from this sh*t. I really wish I had someone that lives around me to help me out lol.
Can you try getting them to idle on the 1 bar first. Maybe you have an issue with your 2 bar sensor?
2844USMC wrote:Can you try getting them to idle on the 1 bar first. Maybe you have an issue with your 2 bar sensor?
yes I could get it to idle with the one bar map. The 2 bar map is brand new so maybe it's my lack of tuning and base 2 bar map tune? The thing is, when I had my car idling with the one bar, my a/f gauge was reading 10.3 so I tried to lean it out and the car would not even stay running.
What tuning software are you running? Can/have you watched the signal for the map sensor in a live scan to verify it is functioning correctly?
I'm using hp tuners standard version. I watch the map signal in the vcm scanner but I am not sure if it is real time or not. I thought I read that you cannot read real-time with hp?
Should be able to watch the map signal in your chart after you start scanning. Should see it at 25 or so while idling and then top off at zero vac when you floor it. Don't quote me on the exact numbers. You should definately see it move when you rev the motor. I know this works, I do it on my car all the time. If you need I can send you a log file to view and you can see what the map sig may look like. Or just run the stock sensor, view the map signal on the chart live then compare it to the 2 bar live. It should look exactly the same except the 2 bar sensor value will read less than the 1 bar.
Bump your IC up to 2.5-3.0.. shifteds tutorial only applies when nothing is being faked..
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cavmania wrote:Bump your IC up to 2.5-3.0.. shifteds tutorial only applies when nothing is being faked..
so should I go back in and enter the stock inj. constant to keep up with the fake 2 bar?
Isn't the highest setting you can go .4 something??? I know I had my car at .48 because I fat fingered one day and it was soooooo rich it wouldn't start. My exhaust turned into a squirt gun. So I'm fairly sure you do not need a 2.5-3.0
ECOHOLIC wrote:So I'm fairly sure you do not need a 2.5-3.0
...And are you faking the 2bar?... BP, try the 2 bar with a 2.5 IC and post what happens
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cavmania wrote:ECOHOLIC wrote:So I'm fairly sure you do not need a 2.5-3.0
...And are you faking the 2bar?... BP, try the 2 bar with a 2.5 IC and post what happens
Seriously, not trying to argue anything. However the largest number I can possibly enter into HPT for my IC is 0.46709. Are you sure that you were not putting in a .25 -.30?
yes I am faking the 2 bar. I had to move the car so i threw the 1 bar back in there and changed the tune back to the 1 bar tune but my a/f guage was still reading 10.3-10.4 although the car idled. I am assuming that it must be my tune. Since I changed all the cells relating to the map, I need to knock the first row down to compensate for the lost resolution. How much do you guys think I should drop off of each cell to try and make up for it?
Set your car back up for the 2 bar. Set the injector constant back up accordingly. Ensure you are reading a map signal in your live scan. Guess at this point I'd check to see what is making it not idle. You haven't really stated that. See if you can get the car to hold a steady idle (by putting your foot on the throttle) and see what the AFR is. Adjust your idle VE table to get it right. If the AFR is good and it is still not idling make sure the timing isn't doing anything crazy.
Also it does sometimes take a minute to re-learn the idle. So make sure to give it a chance. Don't be afraid to try it for a few miutes. Just keep a close eye on the AFR, knock, timing , etc. The important stuff so you don't blow up! and you should be fine.
